Aluminium, Mechanical Engineering

ALUMINIUM

Aluminium was first generated in year of 1825. Presently it is generated in quantity second only to steel. This is the most abundant metallic element on the crust of the earth simply comprising about 8 percent of the crust. Bauxite, Aluminium's hydrous oxide and some other oxides, is the principal ore of aluminium. Through electrolytic process, Aluminium is extracted from its ore mainly. The ore is first washed off to eliminate clay and dirt; the ore is crushed into powder and treated along with hot sodium hydroxide as caustic soda to eliminate impurities. Alumina or the oxide of aluminium extracted from this solution is dissolved in molten aluminium fluroride and sodium fluoride bath at 940-980oC. This mixture after that subjected to direct current electrolysis via passing direct current between carbon cathode and anode. The metallic aluminium forms in liquid state and goes under to bottom of the cell. From time to time, this liquid aluminium is tapped off. The aluminium so obtained is 99.5 to 99.9 percent pure along with iron and silicon as the main impurities.

Aluminium then is obtained to large refractory lined furnaces for refining before casting. The chlorine gas is employed as purging agent to eliminate the dissolved hydrogen gas, and the liquid metal surface is skimmed off to eliminate oxidized metal. The molten metal is next that cast into ingots for rolling or remelting.

Posted Date: 2/26/2013 7:02:30 AM | Location : United States







Related Discussions:- Aluminium, Assignment Help, Ask Question on Aluminium, Get Answer, Expert's Help, Aluminium Discussions

Write discussion on Aluminium
Your posts are moderated
Related Questions
The crank shaft of a high speed pump has a parallel shaft of 2.5 cm diameter and 48 cm in length. It carries three eccentrics each of 6 cm in diameter and uniform thickness of 1.8

The first laboratory report, covering the two-part exercise involving tension testing and stress concentrations is due in lab two weeks after the conclusion of fatigue testing.

Working Principle of Ignition System: An alternating current (AC) is generated when a magnet moves between two stationary coils. In a magneto, a coil of wires moves between two m

What is Time-Study ? How the standard time is determined in Time-Study ? What are the Merit-Rating ? Illustrate various methods of Merit-Rating. Describe the Break-Even-Analy


a) What is method study. Define various stages of method study. b) What are main techniques used to study path of movement in method study. a) Discuss the process to establis

how to e solve motion of followers in simple harmonic motion. what is the angle thita?

Ask question #MiThe steam that leaves the super-heater is expanded from 130bar at 535°C to 25.2bar at 310°C in a high pressure turbine. The steam from the exit of the HP turbine is

Marshalling Yard: Function The marshalling yard is a facility where goods wagons are sorted out for being dispatched to different stations. After being sorted out, th

A light cantilever of rectangular section (5cm deep and 2.5 cm wide) has a mass fixed at its free end. Find the ratio of frequency of free lateral vibration in vertical plane to th